2021/2/both.nim

@@ -0,0 +1,32 @@
+import
+  ../../adventofcode,
+  strutils,
+  strformat
+
+let input = adventofcode.getInput(2021, 2)
+let lines = input.splitLines()[0 .. ^2]
+
+var horizontalPosition = 0
+var depth = 0
+when defined(second):
+  var aim = 0
+
+for line in lines:
+  var command = line.split(" ")
+  case command[0]:
+    of "forward":
+      horizontalPosition += command[1].parseInt()
+      when defined(second):
+        depth += aim * command[1].parseInt()
+    of "up":
+      when defined(second):
+        aim -= command[1].parseInt()
+      else:
+        depth -= command[1].parseInt()
+    of "down":
+      when defined(second):
+        aim += command[1].parseInt()
+      else:
+        depth += command[1].parseInt()
+
+echo fmt"Answer: {horizontalPosition * depth}"

2021/2/first.nim

@@ -1,22 +0,0 @@
-import
-  ../../adventofcode,
-  strutils,
-  strformat
-
-let input = adventofcode.getInput(2021, 2)
-let lines = input.splitLines()[0 .. ^2]
-
-var horizontalPosition = 0
-var depth = 0
-
-for line in lines:
-  var command = line.split(" ")
-  case command[0]:
-    of "forward":
-      horizontalPosition += command[1].parseInt()
-    of "up":
-      depth -= command[1].parseInt()
-    of "down":
-      depth += command[1].parseInt()
-
-echo fmt"Answer: {horizontalPosition * depth}"

2021/2/second.nim

@@ -1,24 +0,0 @@
-import
-  ../../adventofcode,
-  strutils,
-  strformat
-
-let input = adventofcode.getInput(2021, 2)
-let lines = input.splitLines()[0 .. ^2]
-
-var horizontalPosition = 0
-var depth = 0
-var aim = 0
-
-for line in lines:
-  var command = line.split(" ")
-  case command[0]:
-    of "forward":
-      horizontalPosition += command[1].parseInt()
-      depth += aim * command[1].parseInt()
-    of "up":
-      aim -= command[1].parseInt()
-    of "down":
-      aim += command[1].parseInt()
-
-echo fmt"Answer: {horizontalPosition * depth}"

2021/5/both.nim

@@ -10,7 +10,7 @@ type
   Grid = TableRef[Point, int]
 
   HydrothermalVent = object
-    x1, x2, y1, y2: int
+    x1, y1, x2, y2: int
 
   Point = object
     x, y: int
@@ -33,11 +33,10 @@ proc hash(p: Point): Hash =
     else: A + B * B
 
 proc getPoints(v: HydrothermalVent): seq[Point] =
-  let xd = max(v.x1, v.x2) - min(v.x1, v.x2)
-  let yd = max(v.y1, v.y2) - min(v.y1, v.y2)
-  when defined(second):
-    let xoffset = v.x2 - v.x1
-    let yoffset = v.y2 - v.y1
+  let xOffset = v.x2 - v.x1
+  let yOffset = v.y2 - v.y1
+  let xd = xOffset.abs()
+  let yd = yOffset.abs()
 
   if xd != 0 and v.y1 == v.y2:
     for i in 0 .. xd:
@@ -49,20 +48,17 @@ proc getPoints(v: HydrothermalVent): seq[Point] =
 
   else:
     when defined(second):
-      # TODO:
-      if xoffset < 0:
-        for i in 0 .. xd:
-          result.add Point(
-            x: min(v.x1, v.x2) + i,
-            y: max(v.y1, v.y2) - i
-          )
-      
-      else:
-        for i in 0 .. yd:
-          result.add Point(
-            x: max(v.x1, v.x2) + i,
-            y: min(v.y1, v.y2) + i
-          )
+      assert xd == yd
+
+      for i in 0 .. xd:
+        result.add Point(
+          x:
+            if xOffset > 0: min(v.x1, v.x2) + i
+            else: max(v.x1, v.x2) - i,
+          y:
+            if yOffset > 0: min(v.y1, v.y2) + i
+            else: max(v.y1, v.y2) - i
+        )
   
 proc parseInput(input: string): seq[HydrothermalVent] = 
   for line in input.splitLines()[0 .. ^2]:
@@ -71,11 +67,6 @@ proc parseInput(input: string): seq[HydrothermalVent] =
       x1: coords[0][0], y1: coords[0][1], x2: coords[1][0], y2: coords[1][1] 
     )
     
-static:
-  let dummyVent = HydrothermalVent(x1: 9, y1: 7, x2: 7, y2: 9)
-  for point in dummyVent.getPoints():
-    echo $point
-  
 let input = adventofcode.getInput(2021, 5)
 let vents = input.parseInput()
 let grid = Grid()

2021/6/both.nim

@@ -0,0 +1,56 @@
+import
+  ../../adventofcode,
+  math,
+  sequtils,
+  strutils,
+  strformat,
+  tables
+  
+type
+  Cycle = int
+
+let input = adventofcode.getInput(2021, 6)
+let inputLine = input.splitLines()[0]
+
+var days = 0
+var fishes: Table[Cycle, int]
+for i in 0 .. 8:
+  fishes[i] = 0
+
+proc parseInput() =
+  let cycles = inputLine.split(",").mapIt(it.parseInt())
+  for cycle in cycles:
+    fishes[cycle] += 1
+
+proc newDay() =
+  days += 1
+  
+  var temporaryBox: Table[Cycle, int]
+  for i in 0 .. 8:
+    temporaryBox[i] = 0
+
+  for cycle in [8, 7, 6, 5, 4, 3, 2, 1]:
+    let count = fishes[cycle]
+    fishes[cycle] -= count
+    temporaryBox[cycle - 1] += count
+    
+  block cycle0:
+    let count = fishes[0]
+    fishes[0] -= count
+    temporaryBox[6] += count
+    temporaryBox[8] += count
+    
+  for cycle in temporaryBox.keys():
+    fishes[cycle] += temporaryBox[cycle]
+      
+when isMainModule:
+  const simulateDays =
+    when defined(second): 256
+    else: 80
+
+  parseInput()
+  for i in 1 .. simulateDays:
+    newDay()
+
+  echo fmt"{days} days passed."
+  echo fmt"Answer: {math.sum toSeq fishes.values()}"

adventofcode.nim

@@ -3,17 +3,18 @@ import
   os,
   strformat
   
-let session = os.getEnv("SESSION")
-if session == "":
-  echo "Missing SESSION environment variable."
-  quit 1
-
 proc getInput*(year, day: int): string =
   try:
     let input = readFile(getCurrentDir() / "input.txt")
     
     return input
   except IOError:
+    echo "adventofcode> Missing input.txt. Downloading..."
+    let session = os.getEnv("SESSION")
+    if session == "":
+      echo "adventofcode> Unable to download without the SESSION environment variable."
+      quit 1
+
     let client = newHttpClient()
     client.headers = newHttpHeaders({ "Cookie": fmt"session={session}" })
 

license.txt

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 Danny Harpigny
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.